Gunsmithing Freebore/throating for 90gr VLD?

[Mr Flannel]

Gents

I shoot a 223 f-class TR rig down here in Aus (Should be called OZ for the gun laws, but that's another story..)

I'm thinking of changing out the barrel from an 8" twist to a 7" so I can run the Berger 90gr VLD at the longer ranges (800,900,1000).

Questions:

I use .100" of freebore for the 80gr Nosler CC HPBT I currently shoot (and that's still not enough), so how much would I realistically need to use for the 90gr Berger VLD to enable me to seat it long enough keep the base of the bullet up at the case neck/shoulder junction and out of the powder column?

Given the longer freebore and increased twist rate, is it possible to continue to shoot the 80gr HPBT accurately? (might continue to use these at shorter ranges - cheaper)

All advice welcomed

 

[manitou210]

Re: Freebore/throating for 90gr VLD?

COL with 90gr Berger VLD 2.600 is what I seat 90gr VLD, but would lenghten throat to 2.640 app on new barrel I have coming.
30" Tru-Flyte 1/7 twist.I chambered my 30" 1/7 twist with a Pacific match reamer. I will use a Wylde next time. Have to run cases through a small base die with barrel I have on gun now.
It will shoot 80gr VLD, 90gr Match and 90gr VLD and I have less wind on at 1000y than .308win with 155.5 bergers and the 185s
manitou

 

[Mr Flannel]

Re: Freebore/throating for 90gr VLD?

Interesting - so what does that mean in freebore terms? How far off or into the lands will you seat the 90gr?

 

[John L]

Re: Freebore/throating for 90gr VLD?

Priest,
Call Dave Kiff at Pacific Tool & Gage. He is the man when it comes to this kind of thing.

 

[Mr Flannel]

Re: Freebore/throating for 90gr VLD?

Thanks man, Jerry Tierney recommended the same thing. I'll drop him a line.

 

[Jkob]

Re: Freebore/throating for 90gr VLD?

Your barrel can be custom throated to any length you need, a common practice with the longer bullets. The smith doing the work only needs to have a dummy round with the requested bullet seated to the OAL you want and the required "jump"; I do it all the time.

 

[John L]

Re: Freebore/throating for 90gr VLD?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Priest</div><div class="ubbcode-body">Thanks man, Jerry Tierney recommended the same thing. I'll drop him a line. </div></div>

Priest,
Calling on the phone is usually a better way to get hold of him.